Designing for Efficiency
Operation Considerations
Operation | Time |
---|---|
Key | 0.2s |
Mouse Point | 1.1s |
Homing | 0.4s |
Times based on GOMS Keystroke Model, presented in The Psychology of Human-Computer Intearction by Card, Moran and Newell.
Other considerations
- Scanning a list (250ms per item) for first-time user
- Practiced pointing in a list
- Tablet reported to have approximately 0.4 keystroke time
Relevant principles
- Fitts's law --- pointing time is a log function of distance / size
- Hick-Hyman law --- selection time is a log function of the number of items (see Figure 1 in Cockburn et al.)